1. Field of the Invention
This invention relates in general to water closet systems, and more particularly, to an improved means to control during the flushing cycle the pressure differential between the inlet and outlet chambers of a diaphragm flush valve used in the water closet system.
2. Prior Art
Flush valves, and in particular flush valves used in the construction of water closets or urinals, have been used for many years. See, for example, U.S. Pat. No. 30,462 issued Oct. 23, 1860. However, the forerunner to one of the most popular modern diaphragm flush valve designs is disclosed in U.S. Pat. No. 1,714,573 issued May 28, 1929, and commonly referred to as a diaphragm flush valve. A modern version of the diaphragm flush valve is disclosed in U.S. Pat. No. 6,227,219 entitled xe2x80x9cFlush Relief Valve Having Improved Vacuum Breakerxe2x80x9d and issued on May 8, 2001 by the inventor herein.
One reoccurring problem with the use of a diaphragm flush valve has been the unacceptable high pressure of the water supply used to operate the flush valve. For a particular diaphragm flush valve used in water closet systems there will be a desired water pressure to the inlet chamber of the flush valve that permits a proper discharge rate to the water closet bowl. For most systems that pressure is about 50 pounds per square inch. Unfortunately, the pressure of the water supply is often too high for the water closet system to properly function.
Prior art attempts to solve this problem have focused on controlling the water supply pressure. These attempts have not been as effective as would be desired. If the water pressure is set too low, then the valve does not get enough water to consistently function properly. A second problem has been in training personnel to correctly adjust the water pressure at the inlet opening of the valve inlet chamber.
Therefore, one object of this invention is to provide an improved water closet system having means to properly maintain the water pressure in the system at levels to achieve the desired water discharge into the water closet bowl.
Another object of this invention is to provide an improved water closet system that is easy to adjust without significant training by the plumber.
Still another object of this invention is to provide an inexpensive means to control the water pressure in a diaphragm flush valve during the flushing cycle.
Other objects and advantages of the invention will become apparent from the ensuing descriptions of the invention.
The problem of excess water pressure at the inlet opening can be substantially overcome by controlling the pressure differential between the inlet and outlet chambers of the flush valve during the flushing cycle. This can be achieved by use of a fluid flow control means positioned between the outlet chamber discharge opening and the vacuum breaker upstream opening.
The type of fluid flow control means can include any fluid flow restricting member that will restrict the discharge water flow from the outlet chamber to the vacuum breaker to the desired rate to achieve a controlled discharge into the water closet bowl. The fluid flow restricting member can include any of the many known fluid control types of valves that could be mounted on one side to the flush valve and on the other side to the discharge pipe containing the vacuum breaker. The fluid flow restricting member could also include a disc having a predetermined cross-sectional area opening positioned at the upstream opening of the vacuum breaker. The fluid flow restricting member could also include a regulating member, such as opposing rotating discs having a composite opening formed by openings in each of the discs that can be aligned to vary the cross-sectional area of the composite opening.